Not sure if I have anything to contribute of substance but I do have some questions haha
Does that calcium ppm seem kind of high ?
Also, when you say your test is limited what does it not provide for data? For example I don't see any N ?
This includes all your usual amendments added to the mix Im assuming since you said you mixed just as if using peat.
Did you per chance get it tested with the peat mix to compare the two ?
Other than those questions, I would only say if its really composted and looks like black dirt it will be rich in bacteria, and shouldn't cause any imbalance or burn the plants. Might just have slightly different characteristics for CEC, porosity, water holding properties etc. But you can adjust your perlite or whatever you use for porosity air aggregate.
Im also making a mix using things from my backyard so like your thinking.